What is a tracepoint ?

Topic Tracepoint Explanation A tracepoint placed in code provides a hook to call a function (probe) that you can provide at runtime. A tracepoint can be “on” (a probe is connected to it) or “off” (no probe is attached). When a tracepoint is “off” it has no effect, except for adding a tiny time penalty …

Endianness .. Little endian .. Big endian.

Topic Endianness Explanation Endianess is the byte order of the number in the computer’s memory. The number can have any size of bits, bu the most common numbers used are 32 bits (4 bytes) and 16 bits (2 bytes). source : http://www.rapidtables.com/prog/endianess.htm Theory Drop In computing, the term endian or endianness refers to the ordering …

ls ( -I option ) do not list implied entries matching shell PATTERN

UNIX Command $ls bp cfg.c cfg.h CVS gtk Makefile sample.cfg simpleproxy.c $ls -I gtk bp cfg.c cfg.h CVS Makefile sample.cfg simpleproxy.c $ls -I gtk CVS Entries Repository Root $ls -I CVS gtk main.c Makefile simpleproxy-gtk.c $ls -I cfg.c bp cfg.h CVS gtk Makefile sample.cfg simpleproxy.c $ls -I bp cfg.c cfg.h CVS gtk Makefile sample.cfg simpleproxy.c …

hung_task_timeout_secs ( modifying system parameters under /proc/sys file tree)

Linux Parameter $cat /proc/sys/kernel/hung_task_timeout_secs 120 $ Parameter Related TEST-MAIL1 ~ #dmesg [cut] “echo 0 > /proc/sys/kernel/hung_task_timeout_secs” disables this message. rm D ffff88107f472c40 0 16705 22512 0x00000000 ffff881014693810 0000000000000086 ffff881000000000 ffff88102013b040 0000000000012c40 ffff880471855fd8 0000000000012c40 ffff880471854010 ffff880471855fd8 0000000000012c40 ffff881017ff8e40 0000000100000000 Call Trace: [] ? schedule_timeout+0x1ed/0x2d0 [] ? dlmlock+0x8a/0xda0 [ocfs2_dlm] [] ? wait_for_common+0x12c/0x1a0 [] ? try_to_wake_up+0x280/0x280 [] ? …

ls ( -i option )

UNIX Command $ls bp cfg.c cfg.h CVS gtk Makefile sample.cfg simpleproxy.c $ls -i 5448322 bp 7569479 cfg.h 5448162 gtk 925726 sample.cfg 7569478 cfg.c 5448150 CVS 8489600 Makefile 5448260 simpleproxy.c $ UNIX Explanation -i, –inode print the index number of each file Theory Drop In computing, an index-node (inode) is a data structure on a traditional …

bubble sort testing… 0.00007 Ver — 8000 No.'s related

$time php bubble.php real 0m30.911s user 0m28.362s sys 0m0.268s $time php bubble.php real 0m32.206s user 0m29.726s sys 0m0.208s $time php bubble.php real 0m30.047s user 0m28.366s sys 0m0.220s $time php bubble.php real 0m30.306s user 0m28.226s sys 0m0.248s $time php bubble.php real 0m29.819s user 0m28.258s sys 0m0.252s $time php bubble.php real 0m30.567s user 0m28.598s sys 0m0.244s $time …